Borate phosphor and white light illumination device utilizing the same

ABSTRACT

Borate phosphors have a formula Zn 1-x-y B 2 O 4 :Eu 3+   x , Bi 3+   y  (wherein 0≦x≦0.6 and 0≦y≦0.6) emit visible light under the excitation of ultraviolet light or blue light, and may be further collocated with different colored phosphors to provide a white light illumination device.

CROSS REFERENCE TO RELATED APPLICATIONS

The present application is a division of prior U.S. application Ser. No.12/132,612 filed Jun. 4, 2008, entitled “BORATE PHOSPHOR AND WHITE LIGHTILLUMINATION DEVICE UTILIZING THE SAME”. The prior U.S. applicationclaims priority of Taiwan Patent Application No. 097109808, filed onMar. 20, 2008, the entirety of which is incorporated by referenceherein.

BACKGROUND

1. Technical field

The present disclosure relates to a borate phosphor, and in particularrelates to a white light illumination device utilizing the same.

2. Description of the Related Art

Commercially available white light illumination devices such as lightemitting diodes (hereinafter LED), have gradually replaced conventionaltungsten lamps or fluorescent lamps due to high luminescence efficiencyand eco-friendliness. For white LEDs, the phosphor composition locatedwithin, is a critical factor determining luminescence efficiency, colorrendering, color temperature, and lifespan of white LEDs.

In general, the excitation light source of conventional phosphors is ashort wavelength ultraviolet light (UV) such as 147 nm, 172 nm, 185 nm,or 254 nm. The phosphors excited by the short wavelength UV have highlight absorption and light transfer efficiency. Compared with phosphorsexcited by short wavelength UV, phosphors excited by long wavelength UVor visible light (350-470 nm) are rare.

SUMMARY

The disclosure provides a borate phosphor having a formula:Ca_(1-x)AlBO₄:M_(x), wherein M is Pr³⁺, Nd³⁺, Eu³⁺, Eu²⁺, Gd³⁺, Tb³⁺,Ce³⁺, Dy³⁺, Yb²⁺, Er³⁺, Sc³⁺, Mn²⁺, Zn²⁺ or combinations thereof, and0≦x≦0.3.

The disclosure also provides a borate phosphor having a formula:Zn_(1-x-y)B₂O₄:Eu³⁺ _(x), Bi³⁺ _(y), wherein 0≦x≦0.6 and 0≦y≦0.6.

The disclosure further provides a white light illumination devicecomprising the borate phosphor as described as above and an excitationlight source, wherein the excitation light source emits 200-400 nm UV or400-470 nm blue light.

A detailed description is given in the following embodiments withreference to the accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

The disclosure can be more fully understood by reading the subsequentdetailed description and examples with references made to theaccompanying drawings, wherein:

FIG. 1 is a photoluminescence excitation spectrum of the borate phosphorCa_(0.93)AlBO₄:Eu³⁺ _(0.07) in one example of the disclosure;

FIG. 2 is a photoluminescence emission spectrum of the borate phosphorCa_(0.93)AlBO₄:Eu³⁺ _(0.07) in one example of the disclosure;

FIG. 3 is a photoluminescence excitation spectrum of the borate phosphorCa_(0.9)AlBO₄:Tb³⁺ _(0.1) in one example of the disclosure;

FIG. 4 is a photoluminescence emission spectrum of the borate phosphorCa_(0.9)AlBO₄:Tb³⁺ _(0.1) in one example of the disclosure;

FIG. 5 is a photoluminescence excitation spectrum of the borate phosphorCa_(0.98)AlBO₄:Mn²⁺ _(0.02) in one example of the disclosure;

FIG. 6 is a photoluminescence emission spectrum of the borate phosphorCa_(0.98)AlBO₄:Mn²⁺ _(0.02) in one example of the disclosure;

FIG. 7 is a photoluminescence excitation spectrum of the borate phosphorCa_(0.98)AlBO₄:Eu²⁺ _(0.02) in one example of the disclosure;

FIG. 8 is a photoluminescence emission spectrum of the borate phosphorCa_(0.98)AlBO₄:Eu²⁺ _(0.02) in one example of the disclosure;

FIG. 9 is a photoluminescence excitation spectrum of the borate phosphorCa_(0.98)AlBO₄:Ce³⁺ _(0.02) in one example of the disclosure;

FIG. 10 is a photoluminescence emission spectrum of the borate phosphorCa_(0.98)AlBO₄:Ce³⁺ _(0.02) in one example of the disclosure;

FIG. 11 is a photoluminescence excitation spectrum of the boratephosphor Zn_(0.9)B₂O₄:Eu³⁺ _(0.1) in one example of the disclosure;

FIG. 12 is a photoluminescence emission spectrum of the borate phosphorZn_(0.9)B₂O₄:Eu³⁺ _(0.1) in one example of the disclosure;

FIG. 13 is a photoluminescence excitation spectrum of the boratephosphor Zn_(0.8)B₂O₄:Eu³⁺ _(0.1), Bi³⁺ _(0.1) in one example of thedisclosure;

FIG. 14 is a photoluminescence emission spectrum of the borate phosphorZn_(0.8)B₂O₄:Eu³⁺ _(0.1), Bi³⁺ _(0.1) in one example of the disclosure;

FIG. 15 is a comparison of photoluminescence intensity and brightness ofCa_(1-x)AlBO₄:Eu³⁺ _(x) with different x ratios in one example of thedisclosure;

FIG. 16 is a comparison of the photoluminescence spectrum between theborate phosphor Ca_(0.93)AlBO₄:Eu³⁺ _(0.07) and Kasei KX681 in oneexample of the disclosure;

FIG. 17 is a comparison of photoluminescence intensity ofZn_(1-x)B₂O₄:Eu³⁺ _(x) with different x ratios in one example of thedisclosure;

FIG. 18 is a comparison of the photoluminescence spectrum between theborate phosphor Zn_(0.9)B₂O₄:Eu³⁺ _(0.1) and Kasei KX681 in one exampleof the disclosure;

FIG. 19 is a comparison of photoluminescence intensity ofZn_(0.9-y)B₂O₄:Eu³⁺ _(0.1), Bi³⁺ _(y) with different y ratios in oneexample of the disclosure; and

FIG. 20 is a comparison of the photoluminescence spectrum between theborate phosphor Zn_(0.9-y)B₂O₄:Eu³⁺ _(0.1), Bi³⁺ _(0.1) and Kasei KX681in one example of the disclosure.

DETAILED DESCRIPTION

The following description is of the best-contemplated mode of carryingout the disclosure. This description is made for the purpose ofillustrating the general principles of the disclosure and should not betaken in a limiting sense. The scope of the disclosure is bestdetermined by reference to the appended claims.

The disclosure provides a borate phosphor, having a formula asCa_(1-x)AlBO₄:M_(x), wherein M is Pr³⁺, Nd³⁺, Eu³⁺, Eu²⁺, Gd³⁺, Tb³⁺,Ce³⁺, D_(Y) ³⁺, Yb²⁺, Er³⁺, Sc³⁺, Mn²⁺, Zn²⁺, or combinations thereof,and 0≦x≦0.3. For example, the borate phosphors can be Ca_(1-x)AlBO₄:Eu³⁺_(x), Ca_(1-x)AlBO₄:Tb³⁺ _(x), Ca_(1-x)AlBO₄:Mn²⁺ _(x),Ca_(1-x)AlBO₄:Eu²⁺ _(x), or Ca_(1-x)AlBO₄:Ce³⁺ _(x).

The disclosure provides a borate phosphor having a formula asZn_(1-x-y)B₂O₄:Eu³⁺ _(x), Bi³⁺ _(x), Bi³⁺ _(y), wherein 0≦x≦0.6 and0≦y≦0.6. When x is zero and only Bi³⁺ is doped, the borate is a bluephosphor. When y is zero and only Eu³⁺ is doped, the borate is a redphosphor. In one embodiment, the borate doped with Eu³⁺ and Bi³⁺ emitsbrighter red light than the borate doped with only Eu³⁺, because theborate doped with Eu³⁺ is not only directly excited by the excitationlight source but also indirectly excited by the blue light from theborate doped with Bi³⁺.

After excited by blue light (400 nm to 470 nm) or UV (200 nm to 400 nm),the borate phosphors may emit visible lights with different wavelength.In addition, the excitation light source of the borate phosphors can bea light-emitting diode or a laser diode.

The method for preparing the described aluminosilicate is by solid-statereaction. First, the appropriate stoichiometry of reagents was weightedaccording to the element molar ratio of the resulting borates. Thereagents containing Ca can be oxide (CaO) or carbonate (CaCO₃). Thereagents containing Al can be oxide such as γ-Al₂O₃. The reagentscontaining Pr³⁺, Nd³⁺, Bi³⁺, Eu³⁺, Eu²⁺, Gd³⁺, Tb³⁺, Ce³⁺, Dy³⁺, Yb²⁺,Er³⁺, Sc³⁺, Mn²⁺, Zn²⁺, or combinations thereof can be chlorides such asEuCl₂ and the likes, fluorides such as CeF₃ and the likes, oxides suchas Mn₃O₄, MnO₂, Eu₂O₃, Bi₂O₃, CeO₂, and the likes, carbonates such asMnCO₃ and the likes, acetates such as Mn(CH₃COO)₂ and the likes, andnitrates such as Ce(NO₃)₃ and the likes. The boron containing reagentsincludes oxides such as boron oxide (B₂O₃) or boric acid (H₃BO₃). Thedescribed reagents were evenly mixed and grinded, and charged in adouble-crucible. The double-crucible was then stuffed by graphite, andthen heated in a high temperature furnace. After sintering at 700-1000°C. for several hours, washing, and heat drying, the described boratephosphors were prepared.

In one embodiment, the borate phosphor emits red light after beingexcited by blue light or UV light. In this embodiment, the boratephosphors may collocate with a UV excitable blue phosphor and a UV orblue light excitable green phosphor. Arranged with a UV excitation lightsource such as light-emitting diode or laser diode, a white lightemitting diode or white laser diode is completed. The described bluephosphor includes BaMgAl₁₀O₁₇:Eu²⁺, (Ba,Sr,Ca)₅(PO₄)₃(F,Cl,Br,OH):Eu²⁺,2SrO*0.84P₂O₅*0.16B₂O₃:Eu²⁺, Sr₂Si₃O₈*2SrCl₂:Eu²⁺,(Mg,Ca,Sr,Ba,Zn)₃B₂O₆:Eu²⁺, and other suitable blue phosphors. Thedescribed green phosphor includes BaMgAl₁₀O₁₇:Eu²⁺,Mn²⁺, SrGa₂S₄:Eu²⁺,(Ca,Sr,Ba)Al₂O₄:Eu²⁺,Mn²⁺, (Ca,Sr,Ba)₄Al₁₄O₂₅:Eu²⁺,Ca₈Mg(SiO₄)₄Cl₂:Eu²⁺,Mn²⁺, and other suitable green phosphors. If theblue, green, and red phosphors are UV excitable, the blue, green, andred phosphors are directly excited by the excitation light source. Ifthe green and red phosphors are blue light excitable, the red and greenphosphors are indirectly excited by blue light from the blue phosphor.The combination and ratio of blue, green and red phosphors are optionalin different applications of direct or indirect excitation.

For the white light illumination device such as described, a white lightemitting diode or white laser diode, and the red/green/blue phosphorscan be evenly mixed in preferable ratio and dispersed in an optical gel.The optical gel containing the phosphors may further seal a near UVexcitation light source such as a chip of a light emitting diode or alaser diode. Note that if UV is selected as the excitation light source,a UV filter or another UV insulator should be arranged externally fromthe white light illumination device to protect user's eyes and skin.

EXAMPLES Example 1

0.93 mol of CaCO₃ (0.4654 g, FW=100.086, commercially available fromALDRICH, 99.99%), 1 mol of Al₂O₃ (0.2549 g, FW=101.961, commerciallyavailable from ALDRICH, 99.99%), 1 mol of B₂O₃ (0.1740 g, FW=69.619,commercially available from STREM, >99.9%), and 0.035 mol of Eu₂O₃(0.0616 g, FW=351.917, commercially available from ALDRICH, 99.9%) wereweighted, evenly mixed and grinded, and charged in a double-crucible.The double-crucible was then stuffed by graphite, and then heated in ahigh temperature furnace. After sintering in air at 1000° C. for about10 hours, washing, filtering, and heat drying, pure phase of the boratephosphor Ca_(0.93)AlBO₄:Eu³⁺ _(0.07) was prepared. The photoluminescenceexcitation and emission spectra of the described product are shown inFIGS. 1 and 2, respectively. The major peak of the excitation band is396 nm, the major peak of the emission band is 621 nm, and the CIEcoordination is (0.54, 0.31).

Example 2

0.90 mol of CaCO₃ (0.4504 g, FW=100.086, commercially available fromALDRICH, 99.99%), 1 mol of Al₂O₃ (0.2549 g, FW=101.961, commerciallyavailable from ALDRICH, 99.99%), 1 mol of B₂O₃ (0.1740 g, FW=69.619,commercially available from STREM, >99.9%), and 0.025 mol of Tb₄O₇(0.0935 g, FW=747.713, commercially available from STREM, 99.9%) wereweighted, evenly mixed and grinded, and charged in a double-crucible.The double-crucible was then stuffed by graphite, and then heated in ahigh temperature furnace. After sintering in air at 1000° C. for about10 hours, washing, filtering, and heat drying, pure phase of the boratephosphor Ca_(0.9)AlBO₄:Tb³⁺ _(0.1) was prepared. The photoluminescenceexcitation and emission spectra of the described product are shown inFIGS. 3 and 4, respectively. The major peak of the excitation band is351 nm, the major peak of the emission band is 543 nm, and the CIEcoordination is (0.36, 0.50).

Example 3

0.98 mol of CaCO₃ (0.4904 g, FW=100.086, commercially available fromALDRICH, 99.99%), 1 mol of Al₂O₃ (0.2549 g, FW=101.961, commerciallyavailable from ALDRICH, 99.99%), 1 mol of B₂O₃ (0.1740 g, FW=69.619,commercially available from STREM, >99.9%), and 0.02 mol of MnO (0.0071g, FW=70.937, commercially available from ALDRICH, 99.99+%) wereweighted, evenly mixed and grinded, and charged in a double-crucible.The double-crucible was then stuffed by graphite, and then heated in ahigh temperature furnace. After sintering in air at 1000° C. for about10 hours, washing, filtering, and heat drying, pure phase of the boratephosphor Ca_(0.98)AlBO₄:Mn²⁺ _(0.02) was prepared. The photoluminescenceexcitation and emission spectra of the described product are shown inFIGS. 5 and 6, respectively. The major peak of the excitation band is407 nm, the major peak of the emission band is 578 nm, and the CIEcoordination is (0.43, 0.41).

Example 4

0.98 mol of CaCO₃ (0.4904 g, FW=100.086, commercially available fromALDRICH, 99.99%), 1 mol of Al₂O₃ (0.2549 g, FW=101.961, commerciallyavailable from ALDRICH, 99.99%), 1 mol of B₂O₃ (0.1740 g, FW=69.619,commercially available from STREM, >99.9%), and 0.01 mol of Eu₂O₃(0.0176 g, FW=351.917, commercially available from ALDRICH, 99.9%) wereweighted, evenly mixed and grinded, and charged in a double-crucible.The double-crucible was then stuffed by graphite, and then heated in ahigh temperature furnace. After sintering in reductive atmosphere (10%H₂/90% N₂) at 1000° C. for about 10 hours, washing, filtering, and heatdrying, pure phase of the borate phosphor Ca_(0.98)AlBO₄:Eu²⁺ _(0.02)was prepared. The photoluminescence excitation and emission spectra ofthe described product are shown in FIGS. 7 and 8, respectively. Themajor peak of the excitation band is 291 nm, the major peak of theemission band is 420 nm, and the CIE coordination is (0.16, 0.03).

Example 5

0.98 mol of CaCO₃ (0.4904 g, FW=100.086, commercially available fromALDRICH, 99.99%), 1 mol of Al₂O₃ (0.2549 g, FW=101.961, commerciallyavailable from ALDRICH, 99.99%), 1 mol of B₂O₃ (0.1740 g, FW=69.619,commercially available from STREM, >99.9%), and 0.02 mol of CeO₂ (0.0172g, FW=172.118, commercially available from STREM, 99.99%) were weighted,evenly mixed and grinded, and charged in a double-crucible. Thedouble-crucible was then stuffed by graphite, and then heated in a hightemperature furnace. After sintering in air at 1000° C. for about 10hours, washing, filtering, and heat drying, pure phase of the boratephosphor Ca_(0.98)AlBO₄:Ce³⁺ _(0.02) was prepared. The photoluminescenceexcitation and emission spectra of the described product are shown inFIGS. 9 and 10, respectively. The major peak of the excitation band is344 nm, the major peak of the emission band is 377 nm, and the CIEcoordination is (0.16, 0.04).

Example 6

0.9 mol of ZnO (0.4504 g, FW=81.389, commercially available from ACROS,99.99%), 2 mol of H₃BO₃ (0.6193 g, FW=61.932, commercially availablefrom STREM, 99.9995%), and 0.05 mol of Eu₂O₃ (0.0880 g, FW=351.917,commercially available from ALDRICH, 99.9%) were weighted, evenly mixedand grinded, and charged in a double-crucible. The double-crucible wasthen stuffed by graphite, and then heated in a high temperature furnace.After sintering in air at 850° C. for about 10 hours, washing,filtering, and heat drying, pure phase of the borate phosphorZn_(0.9)B₂O₄:Eu³⁺ _(0.1) was prepared. The photoluminescence excitationand emission spectra of the described product are shown in FIGS. 11 and12, respectively. The major peak of the excitation band is 393 nm, themajor peak of the emission band is 610 nm, and the CIE coordination is(0.62, 0.35).

Example 7

0.8 mol of ZnO (0.3256 g, FW=81.389, commercially available from ACROS,99.99%), 2 mol of H₃BO₃ (0.6193 g, FW=61.932, commercially availablefrom STREM, 99.9995%), 0.05 mol of Eu₂O₃ (0.0880 g, FW=351.917,commercially available from ALDRICH, 99.9%), and 0.05 mol of Bi₂O₃(0.1165 g, FW=465.957, commercially available from STREM, 99.999%) wereweighted, evenly mixed and grinded, and charged in a double-crucible.The double-crucible was then stuffed by graphite, and then heated in ahigh temperature furnace. After sintering in air at 850° C. for about 10hours, washing, filtering, and heat drying, pure phase of the boratephosphor Zn_(0.8)B₂O₄:Eu³⁺ _(0.1), Bi³⁺ _(0.1) was prepared. Thephotoluminescence excitation and emission spectra of the describedproduct are shown in FIGS. 13 and 14, respectively. The major peak ofthe excitation band is 393 nm, the major peak of the emission band is610 nm, and the CIE coordination is (0.63, 0.36).

Example 8

Similar to Example 1, appropriate stoichiometry of CaCO₃, Al₂O₃, B₂O₃,and Eu₂O₃ were weighted, evenly mixed and grinded, and charged in adouble-crucible. The double-crucible was then stuffed by graphite, andthen heated in a high temperature furnace. After sintering in air at1000° C. for about 10 hours, washing, filtering, and heat drying, purephase of the borate phosphors Ca_(1-x)AlBO₄:Eu³⁺ _(x) with different xratios were prepared. FIG. 15 shows a comparison of photoluminescenceintensity and brightness of Ca_(1-x)AlBO₄:Eu³⁺ _(x) with different xratios (x=0.03, 0.05, 0.07, and 0.09). When x is 0.07 (Example 1), theborate phosphor has the strongest emission brightness andphotoluminescence emission intensity. Comparing with the Kasei KX681(Y₂O₂S:Eu³⁺, CIE coordination (0.66, 0.33), commercially available fromKasei), the borate phosphor Ca_(0.93)AlBO₄:Eu³⁺ _(0.07) in Example 1 hassimilar photoluminescence emission intensity and better colorsaturation. The comparison of the photoluminescence spectrum between theborate phosphor Ca_(0.93)AlBO₄:Eu³⁺ _(0.07) and KX681 is shown in FIG.16. The photoluminescence emission intensity of the borate phosphorCa_(0.93)AlBO₄:Eu³⁺ _(0.07) reached 95% photoluminescence emissionintensity of KX681. The photoluminescence emission integral area of theborate phosphor Ca_(0.93)AlBO₄:Eu³⁺ _(0.07) reached 96%photoluminescence emission integral area of KX681.

Example 9

Similar to Example 6, appropriate stoichiometry of ZnO, H₃BO₃, and Eu₂O₃were weighted, evenly mixed and grinded, and charged in adouble-crucible. The double-crucible was then stuffed by graphite, andthen heated in a high temperature furnace. After sintering in air at850° C. for about 10 hours, washing, filtering, and heat drying, purephase of the borate phosphors Zn_(1-x)B₂O₄:Eu³⁺ _(x) with different xratios were prepared. FIG. 17 shows a comparison of photoluminescenceintensity of Zn_(1-x)B₂O₄:Eu³⁺ _(x) with different x ratios (x=0.01,0.03, 0.05, 0.1, and 0.2). When x is 0.1 (Example 6), the boratephosphor has the strongest photoluminescence emission intensity.Comparing with the Kasei KX681, the borate phosphor Zn_(0.9)B₂O₄:Eu³⁺_(0.1) in Example 6 has similar photoluminescence emission intensity andbetter color saturation. The comparison of the photoluminescencespectrum between the borate phosphor Zn_(0.9)B₂O₄:Eu³⁺ _(0.1) and KX681is shown in FIG. 18.

The photoluminescence emission intensity of the borate phosphorZn_(0.9)B₂O₄:Eu³⁺ _(0.1) reached 83% photoluminescence emissionintensity of KX681. The photoluminescence emission integral area of theborate phosphor Zn_(0.9)B₂O₄:Eu³⁺ _(0.1) reached 80% photoluminescenceemission integral area of KX681.

Example 10

Similar to Example 7, appropriate stoichiometry of ZnO, H₃BO₃, Eu₂O₃,and Bi₂O₃ were weighted, evenly mixed and grinded, and charged in adouble-crucible. The double-crucible was then stuffed by graphite, andthen heated in a high temperature furnace. After sintering in air at850° C. for about 10 hours, washing, filtering, and heat drying, purephase of the borate phosphors Zn_(0.9-y)B₂O₄:Eu³⁺ _(0.1), Bi³⁺ _(y) withdifferent y ratios were prepared. FIG. 19 shows a comparison ofphotoluminescence intensity of Zn_(0.9-y)B₂O₄:Eu³⁺ _(0.1),Bi³⁺ _(y) withdifferent y ratios (y=0.01, 0.02, 0.05, 0.1, 0.15, and 0.2). When y is0.1 (Example 7), the borate phosphor has the strongest photoluminescenceemission intensity. Comparing with the Kasei KX681, the borate phosphorZn_(0.8)B₂O₄:Eu³⁺ _(0.1), Bi³⁺ _(0.1) in Example 7 has similarphotoluminescence emission intensity and better color saturation. Thecomparison of the photoluminescence spectrum between the borate phosphorZn_(0.8)B₂O₄:Eu³⁺ _(0.1), Bi³⁺ _(0.1) and KX681 is shown in FIG. 20. Thephotoluminescence emission intensity of the borate phosphorZn_(0.8)B₂O₄:Eu³⁺ _(0.1), Bi³⁺ _(0.1) reached 94% photoluminescenceemission intensity of KX681. The photoluminescence emission integralarea of the borate phosphor Zn_(0.8)B₂O₄:Eu³⁺ _(0.1), Bi³⁺ _(0.1)reached 104% photoluminescence emission integral area of KX681.

While the disclosure has been described by way of example and in termsof preferred embodiment, it is to be understood that the disclosure isnot limited thereto. To the contrary, it is intended to cover variousmodifications and similar arrangements (as would be apparent to thoseskilled in the art). Therefore, the scope of the appended claims shouldbe accorded the broadest interpretation so as to encompass all suchmodifications and similar arrangements.

1. A borate phosphor, having a formula: Zn_(1-x-y)B₂O₄:Eu³⁺ _(x), Bi³⁺_(y), wherein 0≦x≦0.6, and 0≦y≦0.6.
 2. The borate phosphor as claimed inclaim 1 is Zn_(0.9)B₂O₄:Eu³⁺ _(0.1), wherein the borate phosphor isexcited by 200-400 nm UV or 400-470 nm blue light to emit a red light,and the red light has a major emission peak of about 610 nm and a CIEcoordination of (0.62, 0.35).
 3. The borate phosphor as claimed in claim1 is Zn_(0.8)B₂O₄:Eu³⁺ _(0.1), Bi³⁺ _(0.1), wherein the borate phosphoris excited by 200-400 nm UV or 400-470 nm blue light to emit a redlight, and the red light has a major emission peak of about 610 nm and aCIE coordination of (0.63, 0.36).
 4. A white light illumination device,comprising the borate phosphor as claimed in claim 1 and an excitationlight source, wherein the excitation light source emits 200-400 nm UV or400-470 nm blue light.
 5. The white light illumination device as claimedin claim 4, wherein the excitation light source comprises a lightemitting diode or a laser diode.
 6. The white light illumination deviceas claimed in claim 4, further comprising a blue phosphor and a greenphosphor.
 7. The white light illumination device as claimed in claim 6,wherein the blue phosphor comprises BaMgAl₁₀O₁₇:Eu²⁺,(Ba,Sr,Ca)₅(PO₄)₃(F,Cl,Br,OH):Eu²⁺, 2SrO*0.84P₂O₅*0.16B₂O₃:Eu²⁺,Sr₂Si₃O₈*2SrCl₂:Eu²⁺, or (Mg,Ca,Sr,Ba,Zn)₃B₂O₆:Eu²⁺.
 8. The white lightillumination device as claimed in claim 6, wherein the green phosphorcomprises BaMgAl₁₀O₁₇:Eu²⁺,Mn²⁺, SrGa₂S₄:Eu^(2°),(Ca,Sr,Ba)Al₂O₄:Eu²⁺,Mn²⁺, (Ca,Sr,Ba)₄Al₁₄O₂₅:Eu²⁺, orCa₈Mg(SiO₄)₄Cl₂:Eu²⁺,Mn²⁺.